• Journal of the Korean Society of Safety
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• v.31 no.4
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• pp.104-110
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• 2016

The effect of a partially earth anchored cable system on the structural safety of a long span cable-stayed bridge under seismic and wind loads are examined during construction process. By assuming the FCM (free cantilever method) construction stages with structural vulnerability, a multi-mode spectral analysis and a multi-mode buffeting analysis are performed for specific seismic load and wind load, respectively. Results show that the wind load dominates the structural safety of a cable-stayed bridge during construction. And, the application of a partially earth anchored cable system can enhance structural safety under wind load since the maximum pylon moment in the model with partially earth anchored cable system is reduced by 49% under wind load. In contrast, the maximum pylon moment occurred by seismic load is only decreased by 8%.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.117-122
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• 2003

Cheongdam Bridge in Seoul Metropolitan Subway Line No.7 recently constructed has 180 meters (2@90m) of expansion length of structure (distance between fixed points). Track type is all ballasted track and rail expansion joint is installed at every movable point. However, there is no expansion joint at the transition area between ballasted track ,end deck. By this reason, the rail buckling has been occurred every year and there is actually an abnormal behavior in expansion. In this study, based on the modeling of the Cheongdam Bridge, the element of interacting relationship between track and structure which is influential to track displacement in long-span bridge was analyzed and, finally, the methodology to ensure the continuous-welded rail in Cheongdam Bridge was suggested.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.245-246
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• 2009

This paper presents the development of lightweight aggregate self-consolidating concrete using lightweight aggregates. Lightweight concrete is known for its advantage of reducing the self-weight of the structures, reducing the areas of sectional members as well as making the construction convenient. Thus the construction cost can be saved when applied to structures such as long-span bridge and high rise building. Therefore experimental tests were performed as such mechanical properties and carbonation of self-consolidating concrete using lightweight aggregates.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.143-144
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• 2009

This study is a development of new PSC girder overcomes weakness of the existing PSC girder and has advantage of construction mark, economical efficiency and maintenance. The gole of this study is reducing dead-load and long-span as HWPC girder has same section through hole and multi-prestressing.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.141-146
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• 1998

In the present study, we have developed high strength concrete which is adequate for the long span PC beam above 40 meters. We have selected the most adequate materials for high strength concrete through laboratory tests and in-situ mock-up applications. We verified and decided the best curing condition of high strength concrete, and suggests the optimum mix design of high strength concrete. In the future, we will verify the properties-fresh and hardened concrete- of high strength concrete and its serviceability, and also apply the high strength concrete to newly-constructed real bridge structure.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.466-471
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• 2011

본 연구에서는 장대 현수교 주케이블의 가설시 선형관리를 위한 기초적 연구를 수행하였다. 우선, 포물선 요소 및 탄성현수선 요소의 정식화 과정을 검토하고, 각 요소의 적용에 따른 현수교 주케이블 완성계 및 가설계의 형상, 장력, 무응력장 등을 비교검토 하였다. 또한, 탄성현수선의 적용시 주케이블 가설계의 setback량 산정 방법을 제시하였으며, 이에 따른 산정 결과를 유한요소해석 결과와 비교검토 하였다. 최종적으로, 주케이블 가설계의 중앙경간 새그량 변화에 따른 탑정 새들부에서의 미끌림 안정성에 대한 민감도 해석을 수행할 예정이다.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.680-685
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• 1998

Prestressed concrete I-girders were used in the bridge applications in the early 1950s. During the last four decades, the most widely used girder length of bridges have been below 30meters. The main objective of this study is to develope the alternative section for long span bridge which exceed 40 meters. The developed Bulb-Tee girder has a wide bottom flange to enhance the compressive strength and to allow placement of a large number of strands in the bottom flange. New bulb-tee shaped PSC girder sections are proposed in this paper. Splicing the technique for long span bridge girder to reduce the self weight is also proposed.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2081-2082
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• 2000

서강대교와 같은 장경간 교량에 초고압 전력케이블을 설치하는 경우에는 교량의 큰 신축을 흡수하기 위하여 케이블을 장대옵셋으로 설치하는 것이 불가피하게 되고, 장대옵셋 케이블이 균등하게 변형할 수 있도록 신축균등흡수장치를 실증시험을 통하여 국내에서 최초로 개발하고 154kV 중여T/L 구간중 서강대교에 총12기를 설치 완료하였다. 본 고에서는 그 개요를 소개하고자 한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.521-522
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• 2007

A new high strength conductor was designed for long span transmission line with a high nitrogen steel having high tensile strength and non-magnetic properties and high strength AI alloy. The tensile strength of conductor is very important to reduce the sag. The height of electric tower depend on the sag also. More than 36% less of sag was achieved by using ACHR(Aluminum conductor stranded high-nitrogen steel reinforced) instead of conventional ACSR.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.3
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• pp.183-187
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• 2016

Recently, power demand has been increasing every year according to variation of electrical equipments and temperature rise in summer season. So, much more overhead line is being demanded to copy with increasing power demand and operate reliable power system. This paper analysis the characteristics of long span overhead transmission line using special high-tension wire in such as a safety factor, coefficient of elasticity, and the coefficient of linear expansion. Based on the analysis, we proposed the effectiveness of special high-tension wire having much more advantages with respect to height of steel tower and dip compared with conventional ACSR in long span overhead transmission line.